noun 1.Also called pompano, butterfly-shell clam. a small clam,
Donax variabilis, abundant in the intertidal zone of eastern and southern U.S. coastal beaches, having fanlike bands of various hues, the paired empty shells often spread in a butterfly shape.
2.any similar clam, especially of the genus Donax.
3.a soft, whitish rock made up of fragments of marine shells and coral, used as a building material.
Origin: 1830–40, Americanism; <
Spanish: literally, shellfish, equivalent to
Old Spanish coc(a) shellfish (<
Latin concha; see
conch) +
-ina -ine1